81368881875 has 60 divisors (see below), whose sum is σ = 150451621320. Its totient is φ = 42338160000.

The previous prime is 81368881849. The next prime is 81368881883. The reversal of 81368881875 is 57818886318.

It is not a de Polignac number, because 81368881875 - 2¹³ = 81368873683 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 54216 + ... + 407034.

It is an arithmetic number, because the mean of its divisors is an integer number (2507527022).

Almost surely, 2^81368881875 is an apocalyptic number.

81368881875 is a deficient number, since it is larger than the sum of its proper divisors (69082739445).

81368881875 is a wasteful number, since it uses less digits than its factorization.

81368881875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352886 (or 352868 counting only the distinct ones).

The product of its digits is 20643840, while the sum is 63.

The spelling of 81368881875 in words is "eighty-one billion, three hundred sixty-eight million, eight hundred eighty-one thousand, eight hundred seventy-five".